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@@ -626,6 +626,7 @@ See also [Are we (I)DE yet?](https://areweideyet.com/) and [Rust and IDEs](https
 * [danielpclark/array_tool](https://github.com/danielpclark/array_tool) — Array helpers for Rust. Some of the most common methods you would use on Arrays made available on Vectors. Polymorphic implementations for handling most of your use cases. [<img src="https://api.travis-ci.org/danielpclark/array_tool.svg?branch=master">](https://travis-ci.org/danielpclark/array_tool)
 * [fizyk20/generic-array](https://github.com/fizyk20/generic-array) – a hack to allow for arrays sized by typenums [<img src="https://api.travis-ci.org/fizyk20/generic-array.svg?branch=master">](https://travis-ci.org/fizyk20/generic-array)
 * [Nemo157/roaring-rs](https://github.com/Nemo157/roaring-rs) – Roaring Bitmaps in Rust [<img src="https://api.travis-ci.org/Nemo157/roaring-rs.svg?branch=master">](https://travis-ci.org/Nemo157/roaring-rs)
+* [orium/rpds](https://github.com/orium/rpds) [[rpds](https://crates.io/crates/rpds)] — Persistent data structures in Rust. [<img src="https://api.travis-ci.org/orium/rpds.svg?branch=master">](https://travis-ci.org/orium/rpds)
 * [reem/rust-typemap](https://github.com/reem/rust-typemap) — [<img src="https://api.travis-ci.org/reem/rust-typemap.svg?branch=master">](https://travis-ci.org/reem/rust-typemap)
 * [xfix/enum-map](https://github.com/xfix/enum-map) [[enum-map](https://crates.io/crates/enum-map)] — An optimized map implementation for enums using an array to store values. [<img src="https://api.travis-ci.org/xfix/enum-map.svg?branch=master">](https://travis-ci.org/xfix/enum-map)